ALMA

ALMA is an acronym for the Atacama Large Millimetre/submillimetre Array, a telescope currently being constructed at an altitude of 5000 m on Llano de Chajnantor, a plane in the north Chilean Andes. ALMA is an international facility, comprising partners from Europe, Taiwan, Japan, Chile and North America. When it is fully completed in 2012, it will be the largest ground-based telescope the world has ever seen.

The Andean site was chosen due to its favourable climatic conditions. Its high altitude means that at ALMA’s operating wavelengths of 0.3–9.6 mm, the dry atmosphere will be largely transparent. ALMA’s 64 individual 12-m moveable antennae with baselines from 0.15–18 km will provide unprecedented sensitivity, resolution and frequency-coverage at these wavelengths. The typical achievable spatial resolution of 10 milliarcsec is 10 times better than that available with the Very Large Array or Hubble Space Telescope.